Using /31 for router links

Seth Mattinen sethm at
Sat Jan 23 00:53:25 UTC 2010

Joe Provo wrote:
> On Fri, Jan 22, 2010 at 04:08:28PM -0800, Seth Mattinen wrote:
>> In the past I've always used /30's for PTP connection subnets out of old 
>> habit (i.e. Ethernet that won't take unnumbered) but now I'm considering 
>> switching to /31's in order to stretch my IPv4 space further. Has anyone 
>> else does this? Good? Bad? Based on the bit of testing I've done this 
>> shouldn't be a problem since it's only between routers.
> rfc3021 is over 9 years old, so should be no suprise that it works 
> well.  :-)

I'm never surprised anymore by something that should work turning out to 
have some obscure quirk about it, so I figured it was worth asking. ;)


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